On 15/02/2013, at 10:02, greelgorke wrote: > > Am Freitag, 15. Februar 2013 07:08:44 UTC+1 schrieb Jorge: >> On 14/02/2013, at 20:28, Jacob Groundwater wrote: >> > >> > I think the solution to any CPU intensive task is a work queue. Do not mix >> > your IO-bound processes with your CPU-bound processes. Node doesn't suck >> > at CPU-bound tasks, it just can't do IO at the same time. >> >> But a node with -javascript- threads *can* do IO *and* CPU-bound tasks at >> the same time. >> >> > It's not like a threaded app will magically have more CPU to compute with. >> >> Yes it will, in an N cores machine, a node with N threads has ~ N times more >> CPU to compute with. >> >> Even in a single core machine, a node with threads-a-gogo can do any amount >> of -javascript- CPU-bound tasks *and* any IO in parallel, easily and without >> sttutering, something that no node can do without threads-a-gogo. >> >> <https://github.com/xk/node-threads-a-gogo> > > threads-a-gogo and node cluster are only 2 possible solutions.
Node cluster is a completely different thing because a node with any number of heavy cpu-bound tasks running in threads-a-gogo will keep processing any IO requests *IN*PARALLEL* just fine, but in a node-cluster, any node that happens to be running a heavy cpu-bound task will be completelly stalled and unable to do *ANY* IO until the task has finished. For example, say you're serving a page A which is computationally heavy and takes 10 seconds to process, and a page B which isn't: -with threads-a-gogo: no matter what, page B will always be served fast. -with a node cluster: page B will only be served fast IF there's not any pending request for a page A. If there's any previous request for a page A, page B *and* any other pending IO will have to wait until page A is finished. Say you make a node-cluster with 4 nodes, and you get these requests in this order: a-a-a-a-a-a-a-a-b B will take ~ 20 seconds! Now say you instead .create() 4 threads with threads-a-gogo: B won't have to wait for any As, it will be served immediately! IOW: node-cluster does NOT give node the ability to run your code in parallel with the event loop and thus as soon as your code blocks it stalls node completely, UNLIKE the case of a node with threads_a_gogo. > also you can put your heavy calculating routine in a separate module which > runs in a separate process and handles a queue and a worker pool. fork it and > comunicate via process#send. it's a system-internal service process. The thing is that when your code blocks the event loop the node process stalls so you can't communicate with it. To run blocking code and NOT stall node, the only sane solution is threads-a-gogo, not node-cluster. <https://github.com/xk/node-threads-a-gogo> -- Jorge. -- -- Job Board: http://jobs.nodejs.org/ Posting guidelines: https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines You received this message because you are subscribed to the Google Groups "nodejs" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/nodejs?hl=en?hl=en --- You received this message because you are subscribed to the Google Groups "nodejs" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
